Andrew D Paterson

SickKids, Toronto, Ontario, Canada

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Publications (214)1617.35 Total impact

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    ABSTRACT: Non-progressive cerebellar ataxias are a rare group of disorders that comprise approximately 10% of static infantile encephalopathies. We report the identification of mutations in PMPCA in 17 patients from four families affected with cerebellar ataxia, including the large Lebanese family previously described with autosomal recessive cerebellar ataxia and short stature of Norman type and localized to chromosome 9q34 (OMIM #213200). All patients present with non-progressive cerebellar ataxia, and the majority have intellectual disability of variable severity. PMPCA encodes α-MPP, the alpha subunit of mitochondrial processing peptidase, the primary enzyme responsible for the maturation of the vast majority of nuclear-encoded mitochondrial proteins, which is necessary for life at the cellular level. Analysis of lymphoblastoid cells and fibroblasts from patients homozygous for the PMPCA p.Ala377Thr mutation and carriers demonstrate that the mutation impacts both the level of the alpha subunit encoded by PMPCA and the function of mitochondrial processing peptidase. In particular, this mutation impacts the maturation process of frataxin, the protein which is depleted in Friedreich ataxia. This study represents the first time that defects in PMPCA and mitochondrial processing peptidase have been described in association with a disease phenotype in humans. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Brain 03/2015; DOI:10.1093/brain/awv057 · 10.23 Impact Factor
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    ABSTRACT: The Genetics, Environmental, Microbial Project is a multicenter study assessing etiological factors in Crohn's disease by studying healthy first-degree relatives (FDRs) of individuals affected by Crohn's disease. We aimed to evaluate the contribution of genetic, microbial, and environmental factors to the determination of intestinal permeability in healthy FDRs. IP was assessed using the lactulose-mannitol ratio (LacMan ratio). FDRs were genotyped for 167 inflammatory bowel disease-associated single nucleotide polymorphisms. Taxonomic profile of the fecal microbiota was determined by Illumina MiSeq pyrosequencing of 16S ribosomal RNA. The associations of LacMan ratio with demographic factors, inflammatory bowel disease-associated single nucleotide polymorphisms and the fecal microbiota were assessed. One hundred ninety-six white FDRs were included. Eleven percent of FDRs had an elevated LacMan ratio (≥0.03). A multivariate analysis demonstrated that younger subjects and nonsmokers had higher LacMan ratios, P = 3.62 × 10 and P = 0.03, respectively. The LacMan ratio was not significantly heritable, H2r, 0.13, P = 0.13. There was no association between any of the 167 inflammatory bowel disease-associated risk variants and LacMan ratio nor was there a correlation between fecal microbial composition and the LacMan ratio. We did not find LacMan ratio to be significantly heritable suggesting that the contribution of genetic factors to the determination of intestinal permeability in healthy FDRs is modest. Environmental factors, such as smoking, are likely more important determinants. The effect of age on intestinal barrier function has been underappreciated.
    Inflammatory Bowel Diseases 03/2015; DOI:10.1097/MIB.0000000000000323 · 5.48 Impact Factor
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    ABSTRACT: The R620W variant of PTPN22 is one of the major genetic risk factors for several autoimmune disorders including type 1 diabetes (T1D) in humans. In the BioBreeding T1D-prone (BBDP) rat, a single nucleotide polymorphism in Ptpn22 results in an A629T substitution immediately C-terminal to the aliphatic residues central to the Ptpn22-C-terminal Src kinase interaction. This variant exhibits a 50% decrease in C-terminal Src kinase binding affinity and contributes to T cell hyperresponsiveness. Examination of BBDP sublines congenic for the Iddm26.2 locus that includes Ptpn22 has not only shown an expansion of activated CD4(+)25(+) T lymphocytes in animals homozygous for the BBDP allele, consistent with enhanced TCR-mediated signaling, but also a decrease in their proportion of peripheral Foxp3(+) regulatory T cells. Furthermore, clinical assessment of both an F2(BBDP × ACI.1u.Lyp) cohort and Iddm26.2 congenic BBDP sublines has revealed an association of Ptpn22 with T1D. Specifically, in both cases, T1D risk is significantly greater in BBDP Ptpn22 homozygous and heterozygous animals. These findings are consistent with a role for rat Ptpn22 allelic variation within Iddm26.2 in the regulation of T cell responses, and subsequently the risk for development of T1D. Copyright © 2014 by The American Association of Immunologists, Inc.
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    ABSTRACT: We investigated the association of signals from previous GWAS and candidate gene meta-analyses for diabetic retinopathy (DR) or nephropathy (DN), as well as an EPO variant in meta-analyses of severe (SDR) and mild diabetic retinopathy (MDR). Meta-analyses of SDR (≥severe non-proliferative diabetic retinopathy (NPDR) or history of panretinal photocoagulation) and MDR (≥mild NPDR), defined based on seven-field stereoscopic fundus photographs, were performed in two well-characterized type 1 diabetes (T1D) cohorts: the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC, n = 1,304) and Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR, n = 603). Among 34 previous signals for DR, after controlling for multiple testing, no association was replicated in our meta-analyses. rs1571942 and rs12219125 at PLXDC2 locus showed nominally significant (<0.05) association with SDR in the same direction as previous report, as did rs1801282 in PPARG gene with MDR. Among 55 loci previously associated with DN, three showed suggestive associations with SDR in our study without maintaining significance after correction for multiple testing. Of particular interest, rs1617640 (EPO) was not significantly associated with DR status, combined SDR–DN phenotype, time to SDR or time to DN (all P > 0.05). Lack of replication of previous DR hits and EPO despite reasonable statistical power implies that many of these may be false positives. Consistent with pleiotropy, we provide suggestive collective evidence for association between DR and variants previously associated with DN without reaching statistical significance at any single locus. Electronic supplementary material The online version of this article (doi:10.1007/s00439-014-1517-2) contains supplementary material, which is available to authorized users.
    Human Genetics 12/2014; 134(2). DOI:10.1007/s00439-014-1517-2 · 4.52 Impact Factor
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    ABSTRACT: The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal mendelian long-QT syndrome (LQTS). Using a genome-wide association and replication study in up to 100,000 individuals, we identified 35 common variant loci associated with QT interval that collectively explain ∼8-10% of QT-interval variation and highlight the importance of calcium regulation in myocardial repolarization. Rare variant analysis of 6 new QT interval-associated loci in 298 unrelated probands with LQTS identified coding variants not found in controls but of uncertain causality and therefore requiring validation. Several newly identified loci encode proteins that physically interact with other recognized repolarization proteins. Our integration of common variant association, expression and orthogonal protein-protein interaction screens provides new insights into cardiac electrophysiology and identifies new candidate genes for ventricular arrhythmias, LQTS and SCD.
    Nature Genetics 12/2014; DOI:10.1038/ng.3014 · 29.65 Impact Factor
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    ABSTRACT: Copy number variation has emerged as an important cause of phenotypic variation, particularly in relation to some complex disorders. Autism spectrum disorder (ASD) is one such disorder, in which evidence is emerging for an etiological role for some rare penetrant de novo and rare inherited copy number variants (CNVs). De novo variation, however, does not always explain the familial nature of ASD, leaving a gap in our knowledge concerning the heritable genetic causes of this disorder. Extended pedigrees, in which several members have ASD, provide an opportunity to investigate inherited genetic risk factors. In this current study, we recruited 19 extended ASD pedigrees, and, using the Illumina HumanOmni2.5 BeadChip, conducted genome-wide CNV interrogation. We found no definitive evidence of an etiological role for segregating CNVs in these pedigrees, and no evidence that linkage signals in these pedigrees are explained by segregating CNVs. However, a small number of putative de novo variants were transmitted from BAP parents to their ASD offspring, and evidence emerged for a rare duplication CNV at 11p13.3 harboring two putative 'developmental/neuropsychiatric' susceptibility gene(s), GSTP1 and NDUFV1.
    Human Genetics 11/2014; 134(2). DOI:10.1007/s00439-014-1513-6 · 4.52 Impact Factor
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    ABSTRACT: Significant evidence exists for the association between copy number variants (CNVs) and Autism Spectrum Disorder (ASD); however, most of this work has focused solely on the diagnosis of ASD. There is limited understanding of the impact of CNVs on the 'sub-phenotypes' of ASD. The objective of this paper is to evaluate associations between CNVs in differentially brain expressed (DBE) genes or genes previously implicated in ASD/intellectual disability (ASD/ID) and specific sub-phenotypes of ASD. The sample consisted of 1590 cases of European ancestry from the Autism Genome Project (AGP) with a diagnosis of an ASD and at least one rare CNV impacting any gene and a core set of phenotypic measures, including symptom severity, language impairments, seizures, gait disturbances, intelligence quotient (IQ) and adaptive function, as well as paternal and maternal age. Classification analyses using a non-parametric recursive partitioning method (random forests) were employed to define sets of phenotypic characteristics that best classify the CNV-defined groups. There was substantial variation in the classification accuracy of the two sets of genes. The best variables for classification were verbal IQ for the ASD/ID genes, paternal age at birth for the DBE genes and adaptive function for de novo CNVs. CNVs in the ASD/ID list were primarily associated with communication and language domains, whereas CNVs in DBE genes were related to broader manifestations of adaptive function. To our knowledge, this is the first study to examine the associations between sub-phenotypes and CNVs genome-wide in ASD. This work highlights the importance of examining the diverse sub-phenotypic manifestations of CNVs in ASD, including the specific features, comorbid conditions and clinical correlates of ASD that comprise underlying characteristics of the disorder.Molecular Psychiatry advance online publication, 25 November 2014; doi:10.1038/mp.2014.150.
    Molecular Psychiatry 11/2014; DOI:10.1038/mp.2014.150 · 15.15 Impact Factor
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    David Soave, Andrew Paterson, Lisa Strug, Lei Sun
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    ABSTRACT: We propose a novel and easy-to-implement joint location-scale association testing procedure that can account for complex genetic architecture without explicitly modeling interaction effects, and is suitable for large-scale whole-genome scans and meta-analyses. We focus on Fisher's method and use it to combine evidence from the standard location test and the more recent scale test, and we describe its use for single-variant, gene-set and pathway association analyses.
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    ABSTRACT: To identify genetic variants associated with refractive astigmatism in the general population, meta-analyses of genome-wide association studies were performed for: White Europeans aged at least 25 years (20 cohorts, N = 31,968); Asian subjects aged at least 25 years (7 cohorts, N = 9,295); White Europeans aged <25 years (4 cohorts, N = 5,640); and all independent individuals from the above three samples combined with a sample of Chinese subjects aged <25 years (N = 45,931). Participants were classified as cases with refractive astigmatism if the average cylinder power in their two eyes was at least 1.00 diopter and as controls otherwise. Genome-wide association analysis was carried out for each cohort separately using logistic regression. Meta-analysis was conducted using a fixed effects model. In the older European group the most strongly associated marker was downstream of the neurexin-1 (NRXN1) gene (rs1401327, P = 3.92E-8). No other region reached genome-wide significance, and association signals were lower for the younger European group and Asian group. In the meta-analysis of all cohorts, no marker reached genome-wide significance: The most strongly associated regions were, NRXN1 (rs1401327, P = 2.93E-07), TOX (rs7823467, P = 3.47E-07) and LINC00340 (rs12212674, P = 1.49E-06). For 34 markers identified in prior GWAS for spherical equivalent refractive error, the beta coefficients for genotype versus spherical equivalent, and genotype versus refractive astigmatism, were highly correlated (r = -0.59, P = 2.10E-04). This work revealed no consistent or strong genetic signals for refractive astigmatism; however, the TOX gene region previously identified in GWAS for spherical equivalent refractive error was the second most strongly associated region. Analysis of additional markers provided evidence supporting widespread genetic co-susceptibility for spherical and astigmatic refractive errors.
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    ABSTRACT: Mammographic density reflects the amount of stromal and epithelial tissues in relation to adipose tissue in the breast and is a strong risk factor for breast cancer. Here we report the results from meta-analysis of genome-wide association studies (GWAS) of three mammo-graphic density phenotypes: dense area, non-dense area and percent density in up to 7,916 women in stage 1 and an additional 10,379 women in stage 2. We identify genome-wide significant (Po5 Â 10 À 8) loci for dense area (AREG, ESR1, ZNF365, LSP1/TNNT3, IGF1, TMEM184B and SGSM3/MKL1), non-dense area (8p11.23) and percent density (PRDM6, 8p11.23 and TMEM184B). Four of these regions are known breast cancer susceptibility loci, and four additional regions were found to be associated with breast cancer (Po0.05) in a large meta-analysis. These results provide further evidence of a shared genetic basis between mammographic density and breast cancer and illustrate the power of studying intermediate quantitative phenotypes to identify putative disease-susceptibility loci.
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    ABSTRACT: To identify the genetic cause of autosomal-dominant pattern dystrophy (PD) of the retinal pigment epithelium (RPE) in two families.
    Journal of Medical Genetics 10/2014; DOI:10.1136/jmedgenet-2014-102620 · 5.64 Impact Factor
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    ABSTRACT: Refractive error (RE) is a complex, multifactorial disorder characterized by a mismatch between the optical power of the eye and its axial length that causes object images to be focused off the retina. The two major subtypes of RE are myopia (nearsightedness) and hyperopia (farsightedness), which represent opposite ends of the distribution of the quantitative measure of spherical refraction. We performed a fixed effects meta-analysis of genome-wide association results of myopia and hyperopia from 9 studies of European-derived populations: AREDS, KORA, FES, OGP-Talana, MESA, RSI, RSII, RSIII and ERF. One genome-wide significant region was observed for myopia, corresponding to a previously identified myopia locus on 8q12 (p = 1.25610 28), which has been reported by Kiefer et al. as significantly associated with myopia age at onset and Verhoeven et al. as significantly associated to mean spherical-equivalent (MSE) refractive error. We observed two genome-wide significant associations with hyperopia. These regions overlapped with loci on 15q14 (minimum p value = 9.11610 211) and 8q12 (minimum p value 1.82610 211) previously reported for MSE and myopia age at onset. We also used an intermarker linkage-disequilibrium-based method for calculating the effective number of tests in targeted regional replication analyses. We analyzed myopia (which represents the closest phenotype in our data to the one used by Kiefer et al.) and showed replication of 10 additional loci associated with myopia previously reported by Kiefer et al. This is the first replication of these loci using myopia as the trait under analysis. ''Replication-level'' association was also seen between hyperopia and 12 of Kiefer et al.'s published loci. For the loci that show evidence of association to both myopia and hyperopia, the estimated effect of the risk alleles were in opposite directions for the two traits. This suggests that these loci are important contributors to variation of refractive error across the distribution.
    PLoS ONE 09/2014; 9(9). DOI:10.1371/journal.pone.0107110 · 3.53 Impact Factor
  • Andrew D Paterson
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    ABSTRACT: The Genetic Analysis Workshops distribute real and simulated human genetic data to allow the development and comparison of methods to detect genetic variants and genes related to biological traits; the results are then presented and discussed at a biennial meeting. The data made available for Genetic Analysis Workshop 18 (GAW18) included whole-genome sequence data for odd-numbered autosomes from 20 large Mexican American pedigrees selected through probands with type 2 diabetes. Real and simulated blood pressure phenotype data were provided to allow the comparison of methods to detect variants and genes associated with blood pressure. Some of the complexity present in the data includes related individuals, repeated quantitative trait outcomes, covariates, medication effects, pharmacokinetic effects, missing data, admixed population, and imputed genotypes. A wide range of analytic approaches were applied to the data. Contributions that focused only on a subset of up to 155 unrelated subjects from the pedigrees were faced with low power. One recommendation for future analysis is the use of the provided null phenotype to allow comparison of type I error across methods. Collaboration between statistical geneticists and molecular biologists or bioinformaticians would provide helpful input to place variants in genes for gene-based association tests.
    Genetic Epidemiology 09/2014; 38 Suppl 1(S1):S1-4. DOI:10.1002/gepi.21818 · 2.95 Impact Factor
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    ABSTRACT: Little is known about the genetic factors that contribute to familial colorectal cancer type X (FCCX), characterized by hereditary nonpolyposis colorectal carcinoma with no mismatch repair defects. Genetic linkage analysis, exome sequencing, tumor studies, and functional investigations of 4 generations of a FCCX family led to the identification of a truncating germline mutation in RPS20, which encodes a component (S20) of the small ribosomal subunit and is a new colon cancer predisposition gene. The mutation was associated with a defect in pre-rRNA maturation. Our findings show that mutations in a gene encoding a ribosomal protein can predispose individuals to microsatellite-stable colon cancer. Evaluation of additional FCCX families for mutations in RPS20 and other ribosome-associated genes is warranted.
    Gastroenterology 09/2014; 147(3). DOI:10.1053/j.gastro.2014.06.009 · 13.93 Impact Factor
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    ABSTRACT: Aims/hypothesis Skin fluorescence (SF) is a non-invasive marker of AGEs and is associated with the long-term complications of diabetes. SF increases with age and is also greater among individuals with diabetes. A familial correlation of SF suggests that genetics may play a role. We therefore performed parallel genome-wide association studies of SF in two cohorts. Methods Cohort 1 included 1,082 participants, 35–67 years of age with type 1 diabetes. Cohort 2 included 8,721 participants without diabetes, aged 18–90 years. Results rs1495741 was significantly associated with SF in Cohort 1 (p < 6 × 10−10), which is known to tag the NAT2 acetylator phenotype. The fast acetylator genotype was associated with lower SF, explaining up to 15% of the variance. In Cohort 2, the top signal associated with SF (p = 8.3 × 10−42) was rs4921914, also in NAT2, 440 bases upstream of rs1495741 (linkage disequilibrium r 2 = 1.0 for rs4921914 with rs1495741). We replicated these results in two additional cohorts, one with and one without type 1 diabetes. Finally, to understand which compounds are contributing to the NAT2–SF signal, we examined 11 compounds assayed from skin biopsies (n = 198): the fast acetylator genotype was associated with lower levels of the AGEs hydroimidazolones of glyoxal (p = 0.017). Conclusions/interpretation We identified a robust association between NAT2 and SF in people with and without diabetes. Our findings provide proof of principle that genetic variation contributes to interindividual SF and that NAT2 acetylation status plays a major role.
    Diabetologia 08/2014; 57(8). DOI:10.1007/s00125-014-3286-9 · 6.88 Impact Factor
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    ABSTRACT: Pleiotropy, which occurs when a single genetic factor influences multiple phenotypes, is present in many genetic studies of complex human traits. Longitudinal family data, such as the Genetic Analysis Workshop 18 data, combine the features of longitudinal studies in individuals and cross-sectional studies in families, thus providing richer information about the genetic and environmental factors associated with the trait of interest. We recently proposed a Bayesian latent variable methodology for the study of pleiotropy, in the presence of longitudinal and family correlation. The purpose of this work is to evaluate the Bayesian latent variable method in a real data setting using the Genetic Analysis Workshop 18 blood pressure phenotypes and sequenced genotype data. To detect single-nucleotide polymorphisms with pleiotropic effect on both diastolic and systolic blood pressure, we focused on a set of 6 single-nucleotide polymorphisms from chromosome 3 that was reported in the literature to be significantly associated with either diastolic blood pressure or the binary hypertension trait. Our analysis suggests that both diastolic blood pressure and systolic blood pressure are associated with the latent hypertension severity variable, but the analysis did not find any of the 6 single-nucleotide polymorphisms to have statistically significant pleiotropic effect on both diastolic blood pressure and systolic blood pressure.
    BMC proceedings 06/2014; 8(Suppl 1 Genetic Analysis Workshop 18Vanessa Olmo):S77. DOI:10.1186/1753-6561-8-S1-S77
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    ABSTRACT: Grouping variants based on gene mapping can augment the power of rare variant association tests. Weighting or sorting variants based on their expected functional impact can provide additional benefit. We defined groups of prioritized variants based on systematic annotation of Genetic Analysis Workshop 18 (GAW18) single-nucleotide variants; we focused on variants detected by whole genome sequencing, specifically on the high-quality subset presented in the genotype files. First, we divided variants between coding and noncoding. Coding variants are fewer than 1% of the total and are more likely to have a biological effect than noncoding variants. Coding variants were further stratified into protein changing and protein damaging groups based on the effect on protein amino acid sequence. In particular, missense variants predicted to be damaging, splice-site alterations, and stop gains were assigned to the protein damaging category. Impact of noncoding variants is more difficult to predict. We decided to rely uniquely on conservation: we combined (a) the mammalian phastCons Conserved Element and (b) the PhyloP score, which identify conserved intervals and the single-nucleotide position, respectively. This reduced the noncoding variants to a number comparable to coding variants. Finally, using gene structure definition from the widely used RefSeq database, we mapped variants to genes to support association tests that require collapsing rare variants to genes. Companion GAW18 papers used these variant priority groups and gene mapping; one of these paper specifically found evidence of stronger association signal for protein damaging variants.
    BMC proceedings 06/2014; 8(Suppl 1 Genetic Analysis Workshop 18Vanessa Olmo):S11. DOI:10.1186/1753-6561-8-S1-S11
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    Pingzhao Hu, Andrew D Paterson
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    ABSTRACT: Groups of genes assigned to a pathway, also called a module, have similar functions. Finding such modules, and the topology of the changes of the modules over time, is a fundamental problem in understanding the mechanisms of complex diseases. Here we investigated an approach that categorized variants into rare or common and used a hierarchical model to jointly estimate the group effects of the variants in a pathway for identifying enriched pathways over time using whole genome sequencing data and blood pressure data. Our results suggest that the method can identify potentially biologically meaningful genes in modules associated with blood pressure over time.
    BMC proceedings 06/2014; 8(Suppl 1 Genetic Analysis Workshop 18Vanessa Olmo):S106. DOI:10.1186/1753-6561-8-S1-S106
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    ABSTRACT: The focus of our work is to evaluate several recently developed pooled association tests for rare variants and assess the impact of different gene annotation methods and binning strategies on the analyses of rare variants under Genetic Analysis Workshop 18 real and simulated data settings. We considered the sample of 103 unrelated individuals with sequence data, genotypes of rare variants from chromosome 3, real phenotype of hypertension status and simulated phenotypes of systolic blood pressure (SBP) and diastolic blood pressure (DBP), and covariates of age, sex, and the interaction between age and sex. In the analysis of real phenotype data, we did not obtain significant results for any binning strategy; however, we observed a slight deviation of the p-values from the uniform distribution based on the protein-damaging variant grouping strategy. Evaluation of methods using simulated data showed lack of power even at the conservative level of 0.05 for most of the causal genes on chromosome 3. Nevertheless, analysis of MAP4 produced good power for all tests at various levels of the tests for both DBP and SBP. Our results also confirmed that Fisher's method is not only robust but can also improve power over individual pooled linear and quadratic tests and is often better than other robust tests such as SKAT-O.
    BMC proceedings 06/2014; 8(Suppl 1 Genetic Analysis Workshop 18Vanessa Olmo):S9. DOI:10.1186/1753-6561-8-S1-S9
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    ABSTRACT: The 40 Mb T1D susceptibility locus Iddm26 was mapped to chromosome 2 through linkage analysis of a conditioned cross-intercross between the diabetes-prone BBDP and the diabetes-resistant ACI.BBDP-Iddm1,Iddm2 (ACI.1u.Lyp). It is flanked by Iddm32 and Iddm33, which control the kinetics of disease progression. To fine-map Iddm26 and characterize immune phenotypes controlled by this locus, several congenic sublines were generated carrying smaller, overlapping intervals spanning Iddm26 and fragments of Iddm32 and 33. Analysis of disease susceptibility, age of disease onset, and immune phenotypes in these sublines identified subloci regulating these different parameters. Two ACI.1u.Lyp-derived subloci, Iddm26.1 and Iddm26.2, imparted significant protection from diabetes, decreasing the cumulative incidence by as much as 57% and 28%, respectively. Iddm26.2, which overlaps with the human PTPN22 locus, only affected disease susceptibility, whereas Iddm26.1 also significantly affected disease kinetics, delaying T1D onset by more than 10 days compared with the parental BBDP strain. These Iddm26 subloci also regulated various immune phenotypes, including the proportion of splenic macrophages by Iddm26.1, and the proportion of activated T-cells in secondary lymphoid organs by Iddm26.2. The analysis of Iddm26 congenic animals in two different SPF facilities demonstrated that the influence of this locus on T1D is environment-dependent.Genes and Immunity advance online publication, 12 June 2014; doi:10.1038/gene.2014.29.
    Genes and Immunity 06/2014; 15(6). DOI:10.1038/gene.2014.29 · 3.79 Impact Factor

Publication Stats

8k Citations
1,617.35 Total Impact Points

Institutions

  • 2000–2014
    • SickKids
      • • Program in Genetics and Genome Biology
      • • Department of Ophthalmology and Vision Sciences
      Toronto, Ontario, Canada
  • 1995–2014
    • University of Toronto
      • • Department of Social Work
      • • Hospital for Sick Children
      • • Sunnybrook Health Sciences Centre
      • • Department of Psychiatry
      Toronto, Ontario, Canada
    • McMaster University
      Hamilton, Ontario, Canada
    • North York General Hospital
      North York, Ontario, Canada
  • 2009
    • University Health Network
      • Department of Medicine
      Toronto, Ontario, Canada
  • 1999–2000
    • Centre for Addiction and Mental Health
      Toronto, Ontario, Canada
  • 1998
    • Toronto Western Hospital
      Toronto, Ontario, Canada